Foundry molding machine of roll-over type



Dec. 13, 1932. L K 1,890,933

FOUNDRY MOLDING MACHINE OF ROLL-OVER TYPE Filed Dec. 4, 1931 3 Sheets-Sheet 1 Fig. 1.

Q QQ Y E M I E/VTOA" m 923W Dec. 13, 1932. T. w. BULLOCK FOUNDRY MOLDING MACHINE OF ROLL-OVER TYPE Filed Dec. 4, 1931 5 Sheets-Sheet 2 ATTU/P/VL KY Dec. 13, 1932. T. w. BULLOCK 1,390,933

FOUNDRY MOLDING MACHINE OF" ROLL-OVER TYPE Filed Dec. 4, 1931 3 Sheets-Sheet 3 w w M Q a x 4 am KM g Z wflaagfia vv 3 7 -rig 9 I Patented Dec. 13, 1932 UNITED STATES? PATENT OFFICE...

THOMAS WOODWARD BULLOCK, OF RAINHI LL, ENGLAND, ASSIGNOR' T0 BRITISH INSU- a; LATED CABLES LIMITED, OF PRESCOT, ENGLAND, A BRITISH COMPANY V FOUNDRY MOLDING MACHINE 0F ROLL-OVER TYPE Applicationfiled December 4, 1931, Serial No. 578,949, and in Great Britain This invention relates to molding machines of the rollover type. The usual construction of such a machine comprises a vertical frame member from about the middle of which projects a short horizontal shaft, which is held in a hearing so that the frame and the parts attached to it and carried by it may be rotated about a horizontal axis. The frame member carries at its ends two pressure members between which the mold is squeezed. It also carries at one end a power cylinder for applying directly the pressure, usually by hydraulic means. This construction makes the total weight to be carried by the bearing and to be turned about the horizontal axis large and the greater part of this weight is located at one end of the frame and is unbalanced so that a large turning moment must be applied to roll the frame over. In accordance with the present invention I provide an improved construction by which the weight of the frame and its attachments is reduced and a closer approach to balance of the two ends of the frame is obtained. The new construction also provides for an advantageous arrangement of the operating mechanism.

In the improved construction the power device by which the compression of the mold is effected is mounted in the horizontal projecting part of the frame, that is the part which is directly supported by the bearing, and the transmission from this actuating device to the pressing member is carried out by a system of levers preferably forming a toggle mechanism, links of which extend to the ends of the frame and there produce relative motion between the two press ng members (the table and the presser head) These two members may be both moved relative to the frameor one only of these may be moved, the other being fixed in position on the frame. An arrangement in which the table is fixed inposition on the frame and the presser head only is moved, has constructional advantages.

It will be seen that with such an arrange- December 23, 1980.

ment the heavy operating device is placed in such a position that its weight is mostreadily supported by bearings and it produces no unbalance of the frame and requires no large turning moment to produce a quick roll-over 1 of the machine. The toggle mechanism in itself has the advantage that when compressing the mold it gives a very heavy pressure accompanied by slow movement in the final stage of compression and that it gives a slow movement at the commencement of the withdrawal of the pattern from the mold.

The. operating mechanism will, in general, be arranged most conveniently to produce a horizontal stroke applied, for instance, to a rod moving on the axis about which the machine turns and acting upon the centre of a pair of toggle links which can conveniently be housed in the vertical member of the frame and extend to the ends thereof. The power device may be of any suitable kind, it may, for instance, be a pneumatic or hydraulic cylinder; The construction is, however, particularly suitable for use with an, electromagnetic actuating device such, for instance, as an electro-magnet and armature or a solenoid and core. Such devices must obviously be designed so as to be capable of giving the maximum pressure, which occurs at the end of the stroke. When arranging for direct actuation of the pressure member it is found that the. relation of the pressure exerted by ble its mova the device to the position of from that of member follows a different law the resistance offered by the mold to compression at the different stages of compression. The difference is such that there is a surplus driving force in the greater part of the stroke,

tending to produce undesirably rapid accelerat ons, unless some additionalcontrol device such as a dash-pot is used. By interposing a toggle linkage between the actuating device and the pressing members the pressing force exerted on the pressing members may be made to approximate more closely to the resistance to compression offered by the mold throughout the stroke so that a dash-pot be comes unnecessary or can be reduced in effect.

A roll-over type molding machine having an electro-magnetic actuating device and embodying the principles of the invention as set forth, is illustrated by way of example in the accompanying drawings, wherein Figure 1 is a part-sectional elevation of the complete machine,

Figure 2 is a part-sectional elevation of the molding machine proper in the reverse or rolled-over position,

Figure 3 is a sectional elevation of a detail of the molding machine to a larger scale; and

Figure 4 is a of the machine.

The frame of the molding machine consists of a hollow vertical arm 1 having at its upper end a horizontal extension 2 which accommodates the stem or tail rod 3 of a presser head 4. At the lower end of the frame 1 is mounted the molding table 5, this being supported on a horizontal arm 6 which is itself swivelly attached to the vertical frame 1 by means of a cvlindrical extension or bearing 7. The molding table 5 being so mounted may be swung into position in line with the presser head 4. or swung completely away from this position. To the outer end of the arm 6 is bolted a vertical standard 3 to which is pivotally connected a tie rod 9, the upper end engaging with a forked recess 10 at the outer end of the arm 2. A hand operated catch 11 engages with the nroiecting end of the tie rod 9 and serves to facilitate the disconnection of the tie rod from the forked recess 10. this disconnection being necessarv to allow the lower arm 6 to be swung aside. The molding table 5 is supported upon the arm 6 by means of a screw-threaded spindle 62 hav- 'ing a lock-nut 63 wherebv the height of the tabl may be adiusted according to the space required above it for the accommodation of the moldin a accessories.

The vertical arm 1 has a flanged opening 12 where t is bolted to a horizontal steel cylinder 13 which is'rotatably supported upon a pedestal 14. The pedestal is provided with a bracket 15 carrying a bearing 16 which engages a rearward cylindrical extension 1? of the steel cylinder 13. The forward end of the cylin der 13 is supported upon two rollers 18, one only of which is illustrated in F igure 1. The steel cylinder 13 forms the outer part of the magnetic circuit of an electromagnetic actuating device contained therein. This device comprises a solenoid 19 in the centre of which works moving core 20. The rearward end of the moving core 29 works within the cylindrical extension 17 of the cylinder 13, which having a closed end serves as a dash-pot.

Within a recess formed in the forward end plan view of thetop portion of the moving core 20 is pivotally attached a link member or plunger 23 which passes freely through the centre of a fixed core 22 and through the flanged opening 12 in the vertical arm 1, the forward end of the said member 23 being pivotally connected with a toggle linkage consisting of the levers 24 and The lower lever 24: is pivotally anchored at the bottom end of the vertical arm 1, the

upper end of the lever 25 being connected to a horizontal lever 26 which is pivotally supported by a forked link 27 pivotally suspended between two shoulder-pieces or brackets 28 formed integral with the horizontal eX- tension 2.

The stem 3 of the presser head 4 slides and can be locked within a sleeve 29 which is permanently and pivotally engaged by means of two pins 30 with the forked end of the horizontal lever 26. Means for locking together the stem 3 and the sleeve 29 consists of a conical plug 31 (Figure 3) which passes through a hole in the sleeve 29 and engages with one of two conical recesses in the stem 3. an upper recess 33 and a lower recess 34. The movement of the conical plug 31 is controlled by a hand-wheel 35, located at the outer end of the upper arm or extension 2 of the molding machine frame in a readily accessible position, and actuating a screw-threaded shaft 36 carrying the plug and housed in a shaft 37 which is made integral or rigidly connected with an outer sleeve surrounding the sleeve 29 and embraced-by the forked end of the lever 26. The two pins 30 serving to connect the sleeve 29 with the forked end of the lever 26, as shown in Figure 1, pass through this outer sleeve 60 thereby ensuring that the plug look ing device and hand-operating mechanism move vertically with the sleeve 29. The sleeve 29 is carried in a bearing 38 in the upper arm 2 so that it can slide whilst main taining correct alignment.

In operating the machine the molding table 5 is swung aside so as to be clear of the press-er head 1, and the pattern 39, the molding box 40 with a sand frame ll and the neoessarv sand are placed in position on the table. The presser head 4 is at this stage in the top position as indicated at A in Figure 1, the plug 31 being engaged with the lower recess 34. The table 5 is then swung back under the presser head 4, the tie rod 9 is connected with the outer end of the extension 2, and the presser head 4 is allowed to fall b gravity to its lower operative position in the sleeve 29, indicated by B in Figure 1, the conical plug 31 engaging with the uppermost recess 33. The pressing operation is effected by the horizontal movement of the movable cor-e 20 within the solenoid 19, which movement is transmitted, by means of the toggle mechanism comprising the levers 23, 24 and 25, to raise the rearward end and lower the forward forked end of the horizontal lever 26 to produce a downward pressing movement of the presser head 4. The position of the toggle linkage and the associated mechanism at the end of the pressure stroke is illustrated in Figure 1 by the broken lines, the lower position of the presser head being indicated at C. Before the pressure is relaxed the machine is rotated through 180 into the position illustrated in Figure 2. This operation is effected by means of an electric motor 42, housed within the pedestal 14, and provided with a worm gear 43 driving a horizontal shaft 44 upon which is mounted a spur wheel 45 engaging with a gear wheel 46, the latter being bolted to the cylinder 13 which being rotated about its horizontal axis carries with it the molding machine proper to which it is bolted.

At this point the mold 47 is in the top position indicated in Figure 2. The compressive force being released, the combined weight of the presser head 4 and the component parts now supported thereon act upon the lever 26, and cause the toggle mechanism and moving core 20 to return to their original position, the presser head returning from position G to position B. This movement is controlled by the braking action of the closed end 49 of the sleeve 29 Within a dash-pot 48 attached to the top of the frame 2. The mold 47 is brought out of direct contact with the pattern 39 by this short primary movement of the presser head 4. By means ofthe hand wheel 35 the locking connection between the .stem 3 and the sleeve 29 is broken, thereby allowing the presser head 4 and mold 47 to fall under their own weight as the stem 3 slides through the sleeve 29 to its other operative position, the presser head now being in its original position A. This further, and much more extensive movement, the speed of which is controlled by the movement of a piston head 61 (Figures 1 and 3) formed on the end of the stem 3 Working within the dash-pot formed by the closed-end of the sleeve 29, serves to separate completely the pattern from the mold. The mold is removed from the machine, the presser head 4 is locked in position by means of the hand wheel 35 and the machine rolled back to its initial position in readiness for a similar cycle of operations.

WVhat I claim as my invention and desire to secure by Letters Patent is 1. A molding machine of the roll-over type comprising a frame, a horizontal projecting portion on said frame, a bearing rotatably supporting said projecting portion, an electromagnetic device mounted in said projecting portion, a pair of relatively movable pressing members carried by the frame, a toggle mechanism connecting said electromagnetic device with one of the pressing members and transmitting the pressing movement from said device to said pressing member.

comprising a "frame,

'2. A molding machine of the roll-over type a horizontal projecting portion on said frame, a bearing rotatably supportingsaid projecting portion, a motor device'mounted 'insaid projecting portion, :a pair of relatively movable pressing anember-s carried by the frame, asystem of-levers connected 'to the motor device :and to one of the pressing members for transmitting the pressing movement from the motor device to said pressing member :and a readily disconnectible coupling device formingftheloonnec tion between said lever system and said pressing member and operable to permit the latter to move relative to the former under the influence of gravity.

3. A molding machine of the roll-over type, comprising a frame, a horizontal projecting portion on said frame,

tion, a motor device mounted in said projecting portion, a pair of relatively movable pressing members carried by the frame, a toggle mechanism connecting the motor device with one of the pressing members and a manually operable coupling device forming the connection between said toggle mechanism and said pressing member, the said coupling device comprising a sleeve connected with the toggle mechanism and a stem connected with the pressing member and slidable in said sleeve and a locking member engaging said sleeve and said stem.

4. A molding machine of the roll-over type comprising a frame, means for rotatably supporting said frame, a motor device attached to said frame and moving therewith, a pair of V pressing members mounted in said frame so as to be relatively movable, a lever system connected with said motor device and a sleeve slidably mounted in the frame and operatively connected with said lever system, a stem attached to one of the pressing members and slidable in said sleeve, locking means for connect-ing said sleeve and said stem as required,

the pressing movement from the motor device to said pressing member to form the mold.

6. A molding machine of the roll-over type comprising a frame, a horizontal projecting portion on said frame, supporting said projecting portion, a reciproa bearing rotatably supporting .said projecting porj a bearing rotatably a housing on said frame serving as a dash-pot V hers for transmitting the catory motor device mounted in said projecting portion and having its working stroke the sald bearing, a

parallel with the axis of pair of relatively movable pressing members carried by the frame and serving to form the mold and a system of levers connected to the motor device and to one of the pressing mempressing movement from the motor device to said pressing memher to form the mold.

In testimony whereof I afiix my signature. THOMAS WOODWVARD BULLOCK. 

